This invention relates to compositions useful as low calorie fat materials. The invention further relates to the fat materials in low calorie foods and as a method for reducing serum cholesterol.
One of the most common metabolic problems among people today is obesity. This condition is primarily due to ingestion of a greater number of calories than are expended. Fat is the most concentrated form of energy in the diet, with each gram of fat supplying approximately 9 calories. Overall, fat constitutes about 40% of the total calories in the diet.
Triglycerides constitute about 90% of the total fat consumed in the average diet. One method by which the caloric value of edible fat could be lowered would be to decrease the amount of triglyceride that is absorbed in the human system since the usual edible triglyceride fats are almost completely absorbed (see Lipids, 2, H. J. Deuel, Interscience Publishers, Inc., New York 1955, page 215). A low calorie fat offers a convenient and practical method by which obesity can be prevented or overcome.
An Executive Summary prepared by the Committee on Diet, Nutrition and Cancer, National Academy of Sciences, National Academy Press, Washington, D.C., pp. 4-5 (1982), discusses a possible link between cancer and the intake of fat, i.e., total dietary fat, saturated fat, polyunsaturated fat, and cholesterol. Epidemiological studies have repeatedly shown an association between dietary fat and the occurrence of cancer at several sites, especially the breast, prostate, and large bowel. The data are not entirely consistent, however. Like epidemiological studies, numerous experiments in animals have shown that dietary fats influence tumorigenesis, especially in the breast and the colon.
Pathological conditions which can afflict warmblooded animals can involve the absorption of cholesterol, and associated hypercholesterolemia. For example, epidemiological studies have demonstrated with few exceptions that populations consuming large quantities of saturated fat and cholesterol have a relatively high concentration of serum cholesterol and a high mortality from coronary heart disease. Conversely, the serum cholesterol levels and the mortality from coronary disease are low in populations with a low consumption of saturated fat and cholesterol.
The National Institutes of Health Consensus Development Conference published xe2x80x9cLowering Blood Cholesterol to Prevent Heart Diseasexe2x80x9d, in JAMA, Vol. 253, No. 14, pp. 2080-2086 (1985). It was concluded that elevation of blood cholesterol levels is a major cause of coronary artery disease, and that lowering definitely elevated blood cholesterol levels (specifically, blood levels of low-density lipoprotein [LDL] cholesterol) will reduce the risk of heart attacks caused by coronary heart disease. The Panel recommended appropriate changes in the diet, particularly a reduction in the amount of fat eaten, in order to reduce blood serum cholesterol levels.
Hence, there is a need for ways to reduce the amount of triglyceride fat in the diet, in order to reduce the risks of obesity, cancer, and heart disease.
Low calorie fats which can replace triglycerides are described by Mattson et al. U.S. Pat. No. 3,600,186 to Mattson et al. discloses low calorie, fat-containing, food compositions in which at least a portion of the triglyceride content is replaced with a polyol fatty acid ester, said polyol fatty acid ester having at least four fatty acid ester groups with each fatty acid having from 8 to 22 carbon atoms.
U.S. Pat. No. 4,005,196 to Jandacek et al. discloses the low calorie fat-containing food compositions of the Mattson et al. patent, in combination with sufficient fat-soluble vitamin selected from the group consisting of vitamin A, vitamin D, vitamin E and vitamin K.
U.S. Pat. No. 3,954,976 to Mattson et al. describes pharmaceutical compositions for inhibiting the absorption of cholesterol comprising effective unit dosage amounts of a polyol fatty acid ester having at least four fatty acid ester groups, and a method for treating and/or preventing hypercholesterolemia in an animal comprising systematically administering to such animal successive therapeutically effective doses of said polyol fatty acid ester.
The esters disclosed in the Mattson et al. and Jandacek et al. patents are effective fat substitutes for use in low calorie food products or in pharmaceutical compositions for controlling hypercholesterolemia. Unfortunately, regular ingestion of moderate to high levels of these esters can produce an undesirable xe2x80x9claxativexe2x80x9d effect, namely, leakage of the ester through the anal sphincter. One way to prevent this undesirable laxative effect is to formulate the esters so that they are completely solid at body temperature.
Another means of preventing the undesirable laxative effect is through the addition to the ester of anti-anal leakage agents such as those described in U.S. Pat. No. 4,005,195 to Jandacek. This patent discloses anti-anal leakage agents which include solid fatty acids (melting point 37xc2x0 C. or higher) and their triglyceride source, and solid polyol fatty acid polyesters. Specifically, the agents are selected from the group consisting of: edible C12 and higher saturated fatty acids, and their edible salts; edible, digestible sources of C12 and higher saturated fatty acids; edible, nonabsorbable, nondigestible solid polyol fatty acid polyesters having at least 4 fatty acid ester groups, wherein the polyol is selected from the group consisting of sugars and sugar alcohols containing from 4 to 8 hydroxyl groups and wherein each fatty acid group has from about 8 to about 22 carbon atoms; and edible, nondigestible esters of alpha-branched chain C10-C18 fatty acids.
Completely solid esters, and solid triglycerides or esters used as anti-anal leakage agents, have drawbacks when used in low calorie food compositions. An ester or triglyceride having a high solids content tastes xe2x80x9cwaxyxe2x80x9d in the mouth when ingested. It would be desirable to have a low calorie fat material that is still effective at reducing calories and cholesterol, and that can also have a relatively low solids content so that it does not taste waxy in the mouth. At the same time, it is critical that this fat material not produce an undesirable laxative side effect.
It is therefore an object of the present invention to provide a low calorie fat material for use in low calorie food compositions and as a method for reducing serum cholesterol.
It is another object of this invention to provide a fat material that does not cause a laxative side effect.
It is a further object of this invention to avoid the laxative side effect without the need for use of added anti-anal leakage agents.
These and other objects of the invention will be made clear by the disclosure herein.
The present invention is a composition of matter comprising an edible, wholly or partially nondigestible low calorie fat material having a non-Newtonian pseudoplastic rheology at body temperature. In particular, at 100xc2x0 F. (37.8xc2x0 C.) the fat material has: (a) a viscosity of at least about 2.5 poise at a shear rate of 800 secondsxe2x88x921, a viscosity of at least about 4.0 poise at a shear rate of 100 secondsxe2x88x921, and a viscosity of at least about 15.0 poise at a shear rate of 10 secondsxe2x88x921; (b) a yield point of at least about 2,500 dynes/cm2; (c) a thixotropic area of at least about 0.20xc3x97106 dynes/cm2-sec.; and (d) a liquid/solid stability of at least about 50%.
The composition is useful as a substitute for triglyceride fats in low calorie fat-containing food products, and as a method for reducing serum cholesterol.
Examples of specific low calorie fat materials that can be used in this invention include sugar fatty acid polyesters, polyglycerol fatty acid polyesters, and tricarboxylic acids esterified with fatty alcohols.